Stoichiometric control of electron mobility and 2D superconductivity at LaAlO3-SrTiO3 interfaces
Singh, Gyanendra (Institut de Ciència de Materials de Barcelona)
Guzmán Aluja, Roger (University of Chinese Academy of Sciences)
Saïz, Guilhem (Sorbonne Université)
Zhou, Wu (University of Chinese Academy of Sciences)
Gazquez, Jaume (Institut de Ciència de Materials de Barcelona)
Masoudinia, Fereshteh (Institut de Ciència de Materials de Barcelona)
Winkler, Dag (Chalmers University of Technology. Department of Microtechnology and Nanoscience)
Claeson, Tord (Chalmers University of Technology. Department of Microtechnology and Nanoscience)
Fraxedas, Jordi (Institut Català de Nanociència i Nanotecnologia)
Bergeal, Nicolas (Sorbonne Université)
Herranz Casabona, Gervasi (Institut de Ciència de Materials de Barcelona)
Kalaboukhov, Alexei (Chalmers University of Technology. Department of Microtechnology and Nanoscience)

Date:	2024
Abstract:	SrTiO-based conducting interfaces, which exhibit coexistence of gate-tunable 2D superconductivity and strong Rashba spin-orbit coupling (RSOC), are candidates to host topological superconductive phases. Yet, superconductivity is usually in the dirty limit, which tends to suppress nonconventional pairing and therefore challenges these expectations. Here we report on LaAlO/SrTiO (LAO/STO) interfaces with large mobility and mean free paths comparable to the superconducting coherence length, approaching the clean limit for superconductivity. We further show that the carrier density, mobility, and formation of the superconducting condensate are controlled by the fine-tuning of La/Al chemical ratio in the LAO film. We find a region in the superconducting phase diagram where the critical temperature is not suppressed below the Lifshitz transition, at odds with previous experimental investigations. These findings point out the relevance of achieving a clean-limit regime to enhance the observation of unconventional pairing mechanisms in these systems.
Grants:	Agencia Estatal de Investigación PID2020-118479RB-I00 Agència de Gestió d'Ajuts Universitaris i de Recerca 2019/BP-00207 Agencia Estatal de Investigación CEX2019-000917-S European Commission 801370 European Commission 731473 Agencia Estatal de Investigación TED2021-129857B-I00 Agencia Estatal de Investigación CEX2021-001214-S Agència de Gestió d'Ajuts Universitaris i de Recerca 2021/SGR-00445
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Published in:	Communications Physics, Vol. 7 (May 2024) , art. 149, ISSN 2399-3650

DOI: 10.1038/s42005-024-01644-3

9 p, 3.4 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles